4-甲基苯并-15-冠-5对某些镧系放射性核素的萃取

高等学校化学学报 ›› 1981, Vol. 2 ›› Issue (4): 431.

4-甲基苯并-15-冠-5对某些镧系放射性核素的萃取

王文基, 陈伯忠, 金忠(告羽), 王爱玲

复旦大学物理二系

收稿日期:1980-09-05 出版日期:1981-12-24 发布日期:1981-12-24

THE SOLVENT EXTRACTION OF SEVERAL LANTHANIDE RADIONUCLIDES WITH 4-METHYLBENZO-15-CROWN-5

Wang Wenji, Chen Bozhong, Jin Zhonggao, Wang Ailing

Department of Nuclear Science, Fudan University, Shanghai

Received:1980-09-05 Online:1981-12-24 Published:1981-12-24

摘要/Abstract

摘要： 本文研究了4-甲基苯并-15-冠-5三氯甲烷溶液从苦味酸水溶液中对某些镧系放射性核素(¹⁴⁴Ce、¹⁴⁷Nd、^152+154Eu、¹⁷⁰Tm和¹⁶⁹Yb)的萃取。从斜率分析得出,被萃取状态为1:2:3(金属离子/冠醚/苦味酸根)络合物。在25℃,测定了三价镧系元素的苹取常数(K_ex),得到下列次序:Nd³⁺>Eu³⁺>Ce³⁺>Tm³⁺>Yb³⁺。结果表明,Nd³⁺的离子大小(r=0.995)比其它镧系元素可能更接近4-甲基苯并-15-冠-5环孔的大小。为了将镧系元素与锕系元素作比较,还测定了4-甲基苯并-15-冠-5对Th⁴⁺、UO₂²⁺和Am³⁺的萃取率,所得到的萃取率次序为Th⁴⁺>Am³⁺UO₂²⁺。实验证明,4-甲基苯并-15-冠-5将可能是溶剂萃取法分离铀和钍的有用试剂。溶剂和添加剂影响萃取实验表明,在有机相添加正丁醇或异戊醇,或者以高极性的溶剂(例如,硝基苯)替代三氯甲烷,都能显著地增加对镧系元素的萃取。

Abstract: The solvent extraction of several lanthanide radionuclides(¹⁴⁴Ce, ¹⁴⁷Nd, ^152+154Eu,¹⁷⁰Tm and ¹⁶⁹Yb) from aqueous picric acid solutions with 4-methyl-benzo-15-crown-5 in chloroform has been investigated. The extracted species are found to be 1:2:3 (metal/crown/picrate) complex from slope analysis. The extraction equilibrium constants (K_ex) have been determined at 25°C. The order of K_ex values for trivalent lanthanide is Nd³⁺>Eu³⁺> Ce³⁺ >Tm³⁺ >Yb³⁺. This indicates that the ionic size of Nd³⁺(r = 0.995Å) may better match the cavity size of 4-methylbenzo-15-crown-5 than the ionic sizes of other lanthanides.In order to compare lanthanides with actinides, the extractability of 4-methylbenzo-15-crown-5 for Th⁴⁺, UO₂²⁺ and Am³⁺ has been determined.

TrendMD:

王文基, 陈伯忠, 金忠(告羽), 王爱玲. 4-甲基苯并-15-冠-5对某些镧系放射性核素的萃取. 高等学校化学学报, 1981, 2(4): 431.

Wang Wenji, Chen Bozhong, Jin Zhonggao, Wang Ailing . THE SOLVENT EXTRACTION OF SEVERAL LANTHANIDE RADIONUCLIDES WITH 4-METHYLBENZO-15-CROWN-5. Chem. J. Chinese Universities, 1981, 2(4): 431.